1. Technical Field
The present invention relates to estimating the feature value of a specific component contained in a sample and obtaining the optical spectrum from a multiband image.
2. Description of the Related Art
One proposed structure of a freshness sensor used to evaluate the freshness of fresh foods includes a spectroscope configured to disperse the reflected light from a sample. This prior art freshness sensor converts the reflectance spectrum as the output of the spectroscope into an electric signal by means of an imaging element and compares the electrical signal converted from the reflectance spectrum with a standard spectrum to evaluate the freshness of the sample.
The reflectance spectrum output from the spectroscope represents a feature value of the sample, so that the feature value of the sample can be estimated by utilizing the reflectance spectrum.
This prior art structure enables highly-accurate estimation of the feature value, but requires an expensive, high-performance spectroscope with high wavelength resolution and high S/N ratio, which leads to cost increase.